Injury Risk Evaluation of Brain Concussion in the American Football Using Reproduction Analysis of Accident Cases

Abstract The manual for assessing safety hardware (MASH) defines crash tests to assess the impact performance of highway safety features in frontal and oblique impact events. Within MASH, the risk of injury to the occupant is assessed based on a “flail-space” model that estimates the average deceleration that an unrestrained occupant would experience when contacting the vehicle interior in a MASH crash test and uses the parameter as a surrogate for injury risk. MASH occupant risk criteria, however, are considered conservative in their nature, due to the fact that they are based on unrestrained occupant accelerations. Therefore, there is potential for increasing the maximum limits dictated in MASH for occupant risk evaluation. A frontal full-scale vehicle impact was performed with inclusion of an instrumented anthropomorphic test device (ATD). The scope of this study was to investigate the performance of the flail space model (FSM) in a full-scale crash test compared to the instrumented ATD recorded forces which can more accurately predict the occupant response during a collision event. Additionally, a finite element (FE) model was developed and calibrated against the full-scale crash test. The calibrated model can be used to perform parametric simulations with different testing conditions. Results obtained through this research will be considered for better correlation between vehicle accelerations and occupant injury. This becomes extremely important for designing and evaluating barrier systems that must fit within geometrical site constraints, which do not provide adequate length to redirect test vehicles according to MASH conservative evaluation criteria.

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Similar head impact acceleration measured using instrumented ear patches in a junior rugby union team during matches in comparison with other sports

Journal of Neurosurgery Pediatrics ◽

10.3171/2015.12.peds15605 ◽

2016 ◽

Vol 18 (1) ◽

pp. 65-72 ◽

Cited By ~ 15

Author(s):

Doug A. King ◽

Patria A. Hume ◽

Conor Gissane ◽

Trevor N. Clark

Keyword(s):

Injury Risk ◽

Linear Acceleration ◽

Rugby Union ◽

Head Impact ◽

American Football ◽

Football Players ◽

Head Impacts ◽

Impact Acceleration ◽

The Impact ◽

Rugby Players

OBJECTIVE Direct impact with the head and the inertial loading of the head have been postulated as major mechanisms of head-related injuries, such as concussion. METHODS This descriptive observational study was conducted to quantify the head impact acceleration characteristics in under-9-year-old junior rugby union players in New Zealand. The impact magnitude, frequency, and location were collected with a wireless head impact sensor that was worn by 14 junior rugby players who participated in 4 matches. RESULTS A total of 721 impacts > 10g were recorded. The median (interquartile range [IQR]) number of impacts per player was 46 (IQR 37–58), resulting in 10 (IQR 4–18) impacts to the head per player per match. The median impact magnitudes recorded were 15g (IQR 12g–21g) for linear acceleration and 2296 rad/sec2 (IQR 1352–4152 rad/sec2) for rotational acceleration. CONCLUSIONS There were 121 impacts (16.8%) above the rotational injury risk limit and 1 (0.1%) impact above the linear injury risk limit. The acceleration magnitude and number of head impacts in junior rugby union players were higher than those previously reported in similar age-group sports participants. The median linear acceleration for the under-9-year-old rugby players were similar to 7- to 8-year-old American football players, but lower than 9- to 12-year-old youth American football players. The median rotational accelerations measured were higher than the median and 95th percentiles in youth, high school, and collegiate American football players.

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Finite Element Analysis of Foot and Ankle Impact Injury: Risk Evaluation of Calcaneus and Talus Fracture

PLoS ONE ◽

10.1371/journal.pone.0154435 ◽

2016 ◽

Vol 11 (4) ◽

pp. e0154435 ◽

Cited By ~ 30

Author(s):

Duo Wai-Chi Wong ◽

Wenxin Niu ◽

Yan Wang ◽

Ming Zhang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Risk Evaluation ◽

Injury Risk ◽

Foot And Ankle ◽

Talus Fracture ◽

Element Analysis ◽

Impact Injury

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Impact test comparisons of 20th and 21st century American football helmets

Journal of Neurosurgery ◽

10.3171/2011.9.jns111059 ◽

2012 ◽

Vol 116 (1) ◽

pp. 222-233 ◽

Cited By ~ 35

Author(s):

Adam Bartsch ◽

Edward Benzel ◽

Vincent Miele ◽

Vikas Prakash

Keyword(s):

Head Injury ◽

21St Century ◽

Injury Risk ◽

Diffuse Axonal Injury ◽

Angular Acceleration ◽

Linear Acceleration ◽

Severity Index ◽

Head Impact ◽

American Football ◽

Acute Subdural Hematoma

Object Concussion is the signature American football injury of the 21st century. Modern varsity helmets, as compared with vintage leather helmets, or “leatherheads,” are widely believed to universally improve protection by reducing head impact doses and head injury risk for the 3 million young football players in the US. The object of this study was to compare the head impact doses and injury risks with 11 widely used 21st century varsity helmets and 2 early 20th century leatherheads and to hypothesize what the results might mean for children wearing similar varsity helmets. Methods In an injury biomechanics laboratory, the authors conducted front, oblique front, lateral, oblique rear, and rear head impact tests at 5.0 m/second using helmeted headforms, inducing near- and subconcussive head impact doses on par with approximately the 95th percentile of on-field collision severity. They also calculated impact dose injury risk parameters common to laboratory and on-field traumatic neuromechanics: linear acceleration, angular acceleration, angular velocity, Gadd Severity Index, diffuse axonal injury, acute subdural hematoma, and brain contusion. Results In many instances the head impact doses and head injury risks while wearing vintage leatherheads were comparable to or better than those while wearing several widely used 21st century varsity helmets. Conclusions The authors do not advocate reverting to leather headgear, but they do strongly recommend, especially for young players, instituting helmet safety designs and testing standards, which encourage the minimization of linear and angular impact doses and injury risks in near- and subconcussive head impacts.

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A Base Study to Investigate MASH Conservativeness of Occupant Risk Evaluation

Volume 12: Transportation Systems ◽

10.1115/imece2016-67671 ◽

2016 ◽

Cited By ~ 1

Author(s):

Chiara Silvestri Dobrovolny ◽

Harika Reddy Prodduturu ◽

Dusty R. Arrington ◽

Nathan Schulz ◽

Stefan Hurlebaus ◽

...

Keyword(s):

Risk Evaluation ◽

Injury Risk ◽

Evaluation Criteria ◽

Oblique Impact ◽

Full Scale ◽

Crash Test ◽

Vehicle Interior ◽

Impact Performance ◽

Space Model ◽

The Impact

The Manual for Assessing Safety Hardware (MASH) defines crash tests to assess the impact performance of highway safety features in frontal and oblique impact events. Within MASH, the risk of injury to the occupant is assessed based on a “flail-space” model that estimates the average deceleration that an unrestrained occupant would experience when contacting the vehicle interior in a MASH crash test and uses the parameter as a surrogate for injury risk. MASH occupant risk criteria, however, are considered conservative in their nature, due to the fact that they are based on unrestrained occupant accelerations. Therefore, there is potential for increasing the maximum limits dictated in MASH for occupant risk evaluation. A frontal full-scale vehicle impact was performed with inclusion of an instrumented anthropomorphic test device (ATD). The scope of this study was to investigate the performance of the Flail Space Model in a full scale crash test compared to the instrumented ATD recorded forces which can more accurately predict the occupant response during a collision event. Results obtained through this research will be considered for better correlation between vehicle accelerations and occupant injury. This becomes extremely important for designing and evaluating barrier systems that must fit within geometrical site constraints, which do not provide adequate length to redirect test vehicles according to MASH conservative evaluation criteria.

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Efficacy of Prophylactic Knee Bracing in Sports

The Journal of Knee Surgery ◽

10.1055/s-0041-1740930 ◽

2021 ◽

Author(s):

Kyle Blecha ◽

Clayton W. Nuelle ◽

Patrick A. Smith ◽

James P. Stannard ◽

Richard Ma

Keyword(s):

Sports Medicine ◽

Injury Risk ◽

Cruciate Ligament ◽

Athletic Trainers ◽

Knee Injuries ◽

Frontal Plane ◽

American Football ◽

Work Related ◽

Knee Loading ◽

Anterior Cruciate

AbstractAnterior cruciate ligament (ACL) and medial collateral ligament (MCL) injuries are common knee injuries, which can result from contact and noncontact during sports, recreation, or work-related activities. Prophylactic knee braces (PKBs) have been designed to protect the knee and decrease risk of recurrence of these injuries. Despite their success, PKBs have not been proven to be consistently effective and cost of the device must be evaluated to optimize its use in sports, particularly American football. Biomechanical studies have suggested that increased hip and knee flexion angles may reduce frontal plane loading with bracing which can protect the knee joint. This is essential with knee loading and rotational moments because they are associated with jumping, landing, and pivoting movements. The clinical efficacy of wearing PKBs can have an impact on athletic performance with respect to speed, power, motion, and agility, and these limitations are evident in athletes who are unaccustomed to wearing a PKB. Despite these concerns, use of PKBs increases in patients who have sustained an MCL injury or recovering from an ACL reconstruction surgery. As the evidence continues to evolve in sports medicine, there is limited definitive data to determine their beneficial or detrimental effects on overall injury risk of athletes, therefore leading those recommendations and decisions for their usage in the hands of the athletic trainers and team physicians' experience to determine the specific brace design, brand, fit, and situations for use.

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